WskRestPackageTests 409 conflict related test failure

I suspect combination with HA controllers with round robin load distribution and increased load on Travis VM. Need to investigate further.

```
system.basic.WskRestPackageTests > Wsk Package should allow updating a package STANDARD_OUT
ERROR: deleting asset failed for simplepackagetoupdate: org.scalatest.exceptions.TestFailedException: 409 was not equal to 200

system.basic.WskRestPackageTests > Wsk Package should allow updating a package FAILED
org.scalatest.exceptions.TestFailedException: deletedAll was false some assets were not deleted
```

Start with system.basic.WskRestPackageTests, especially “Wsk Package should allow updating a package,” and reproduce the 409 deletion failure in an HA controller setup with round-robin load distribution. Done means the update test returns 200 and deletedAll is true rather than leaving assets undeleted.

Written by the indexing model from the issue text.